Impact of the handset form factor on inverted-F antennas performance

This paper describes the portability of a multiband antenna design over a printed circuit board (PCB) of different sizes. The antenna consists of two inverted-F antennas (IFA) operating at the same resonance frequency, for multiple-input multiple-output (MIMO) operation. The frequency range presented in this paper is EGSM900 for the low band and IMT-E for the high band, but the results can be extended to bands 5 and 6 with a tunable antenna. Simulations of the antenna behavior with increasing-size ground plane will be compared to the measurements of three common ground plane sizes: the Candybar (100 × 40 mm²), the Smartphone (119 × 59 mm²) and the Tablet (240 × 186 mm²) formats. The investigation shows that the bandwidth requirements are always fulfilled across the devices.